Since rigid frame locomotive size was severely limited by the very sharp curves on the railroad, the next step was to procure an articulated engine. In Europe various designs were being developed for negating sharp curves by allowing axle assemblies to swivel without requiring flexible steam joints and additional cylinders. One of the more successful designs was by Hagans that used a system of "oscillating" levers to connect the rigid set of drivers with the swiveling set. One of these locomotives was purchased for the NE Dundas Tram. This J class engine weighed 42 tonnes or 46 tons.
I have tried to figure out exactly how the Hagans system worked, but I am not there yet. In any event, it appeared to be successful on the NEDT. Hagans engines were well enough liked in Germany, where between the Prussian and Hessian State Railways there were 152 Hagans locomotives in service by 1905.
The Hagans locomotive survived the closure of the NEDT in 1929 when the 2 ft gauge was superseded by an incline railway, but the engine was scrapped in 1949.
To be continued
Edited 1 time(s). Last edit at 01/13/2020 05:47PM by Olaf Rasmussen.